The present invention relates generally to the art of mixing audio source signals to create a final sound product, and more specifically, to a method and apparatus for utilizing visual images of sounds to control and mix the source signals, including any sound effects added thereto, to achieve a desired sound product.
The art of mixing audio source signals is well known and generally referred to as recording engineering. In the recording engineering process, a plurality of source audio signals are input to a multi-channel mixing board (one source signal per channel). The source signals may be analog or digital in nature, such as microphone signals capturing a live performance, or a prerecorded media such as a magnetic tape deck, or a MIDI device (musical instrument digital interface) such as a synthesizer or drum machine. The mixing board permits individual control of gain, effects, pan, and equalization for each channel such that the recording engineer can modify individual channels to achieve the desired total sound effect. For example, it is possible for an individual person to record the performance of a song by recording the playing of different instruments at different times on different channels, then mixing the channels together to produce a stereophonic master recording representative of a group performance of the song. As should be obvious, the sound quality, including volume output, timbral quality, etc., of each channel can vary greatly. Thus, the purpose of the mix is to combine the different instruments, as recorded on different channels, to achieve a total sound effect as determined by the recording engineer.
The recording industry has evolved into the digital world wherein mixing boards and recorders manipulate and store sound digitally. A typical automated mixing board creates digital information that indicates mixing board settings for each channel. Thus, these mixer board settings can be stored digitally for later use to automatically set the mixer board. With the advent of MIDI control, cheaper computer controlled mixing boards have begun to appear. Such systems often include software which shows a picture of a mixing board on the computer screen, and the recording engineer often uses a mouse to manipulate the images of conventional mixing board controls on the screen. The computer then tells the mixer to make the corresponding changes in the actual mixing board.
There are also digital multitrack recorders that record digital signals on tape or hard disk. Such systems are also controlled by using a mouse to manipulate simulated recorder controls on a computer screen.
A new generation of controllers are being developed to replace the mouse for interacting with computers. For example, with a data glove or a virtual reality system one can enter the computer screen environment and make changes with their hands. Further, visual displays are becoming increasingly sophisticated such that one gets the illusion of three-dimensional images on the display. In certain devices, the visual illusion is so good that it could be confused with reality.
Computer processors have just recently achieved sufficient processing speeds to enable a large number of audio signals from a multitrack tape player to be converted into visual information in real time. For example, the Video Phone by Sony includes a Digital Signal Processor (DSP) chip that makes the translation from audio to video fast enough for real time display on a computer monitor.
The concept of using visual images to represent music is not new. Walt Disney Studios might have been the first to do so with its innovative motion picture xe2x80x9cFantasia.xe2x80x9d Likewise, Music Television (MTV) has ushered in an era of music videos that often include abstract visual imaging which is synchronized with the music. However, no one has yet come up with a system for representing the intuitive spatial characteristics of all types of sound with visuals and using those spatial characteristics as a control device for the mix. The multi-level complexities of sound recording are such that very little has even been written about how we visualize sound between a pair of speakers.
The present invention provides a method and apparatus for mixing audio signals having a plurality of audio characteristics associated therewith. According to the invention, a system for mixing a plurality of audio signals includes an audio mixer having a plurality of channels each of which for receiving one of a plurality of audio signals, and for varying audio characteristics of the received audio signal, and for outputing the varied audio signal. An effects processing unit associated with each of the channels adds audio effects to the audio signals. A microcomputer system includes a signal processing unit for transforming each audio signal into an audio signal visual image for display on a video display monitor. Each of the audio signal visual images has visual characteristics that correspond to the audio characteristics of the corresponding audio signal. The signal processing unit also generates audio effect images for display on the video display monitor. The audio effect images have visual characteristics that correspond to audio effects added to the audio signals by the effects processing unit. A user control allows a user to adjust the displayed audio effect images. The effects processing unit changes audio effects added to the audio signals in response to corresponding user adjustments to the displayed audio effect images.
In another aspect of the present invention, a system for mixing a plurality of audio signals includes an audio mixer having a plurality of channels each of which for receiving one of a plurality of audio signals, and for varying audio characteristics of the received audio signal, and for outputing the varied audio signal. A plurality of speakers broadcast the audio signals outputed by the audio mixer. A microcomputer system includes a signal processing unit for transforming each audio signal into an audio signal visual image for display on a video display monitor. Each of the audio signal visual images has visual characteristics that correspond to the audio characteristics of the corresponding audio signal. The audio signal visual images are displayed on the video display monitor within a three dimensional room background image that contains a plurality of speaker images, which represent the plurality of speakers broadcasting the audio signals from the audio mixer. The spatial locations of the audio signal visual images relative to the plurality of speaker images correspond to perceived spatial characteristics of the audio signals broadcasted from the plurality of speakers.
In yet another aspect of the present invention, a system for mixing a plurality of audio signals includes an audio mixer having a plurality of channels each of which for receiving one of a plurality of audio signals, and for varying audio characteristics of the received audio signal, and for outputing the varied audio signal. A microcomputer system includes a signal processing unit for transforming each audio signal into an audio signal visual image for display on a video display monitor. Each of the audio signal visual images has visual characteristics that correspond to the audio characteristics of the corresponding audio signal. The signal processing unit also performs frequency analysis on each of the audio signals to detect even and odd harmonic components thereof. The signal processing unit places a first type of texturing image on the corresponding audio signal visual images for detected even harmonic components, and a second type of texturing image on corresponding audio signal visual images for detected odd harmonic components.
In yet still another aspect of the present invention, a system for mixing a plurality of audio signals includes an audio mixer having a plurality of channels each of which for receiving one of a plurality of audio signals, and for varying audio characteristics of the received audio signal, and for outputing the varied audio signal. A microcomputer system includes a signal processing unit for transforming a selected audio signal into an audio signal visual image for display on a video display monitor. The audio signal visual image is segmented into portions that correspond to preselected frequency ranges. The frequency components of the selected audio signal are dynamically correlated with, and visually displayed with dynamic visual characteristics in, corresponding segmented portions of the audio signal visual image.
In one last aspect of the present invention, an article of manufacture is used with a computer system, an audio mixer having a plurality of channels each of which for receiving one of a plurality of audio signals and for varying audio characteristics of the received audio signal and for outputing the varied audio signal, an effects processing unit associated with each of the channels for adding audio effects to the audio signals, and a plurality of speakers that broadcast the audio signals outputed by the audio mixer. The article of manufacture includes a computer usable medium having computer readable program code means embodied therein for creating visual images of audio signals and audio effects. The computer readable program code means in the article of manufacture includes a computer readable program code means for causing the computer to transform each audio signal into an audio signal visual image and to display the audio signal visual images on a video display monitor. Each of the audio signal visual images has visual characteristics that correspond to the audio characteristics of the corresponding audio signal. The computer readable program code means in the article of manufacture further includes a computer readable program code means for causing the computer to generate audio effect images and to display the audio effect images on the video display monitor. The audio effect images have visual characteristics that correspond to audio effects added to the audio signals by an effects processing unit.
A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description of the invention and the accompanying drawings which set forth an illustrative embodiment in which the principles of the invention are utilized.